Optimize viewport for animation
To optimize viewport performance limit resolution of textures which are assigned to meshes.

Open User Preferences > System tab > textures category (scroll down) > Limit Size. You can choose appropriate value from the dropdown list, where Off is set by default. Read more about limiting size of textures displayed in the viewport in manual.



In the example below limit is disabled first and texture isn't affected. Then limit is set to lowest value (126 px) for demostration purposes which makes textures become blurry and less visible.



To show textures on your objects in viewport follow steps from this question - How to show textures in the 3D View editor? which depend on render engine.